Biosynthetic studies on terpenoids produced by Actinomycetes by focusing on the nonmevalonate pathway

我们得到了以下结果。1.标记实验证明，雪白链霉菌产生的新生霉素是通过非甲羟戊酸途径生物合成的.游动放线菌BE-40644产生的萜烯部分是通过甲羟戊酸途径合成的，而细胞膜成分甲基萘醌是通过非甲羟戊酸途径合成的.从产气链霉菌CL 190中分离纯化HMG CoA还原酶，并克隆其相关基因.从大肠杆菌中分离纯化了非甲羟戊酸途径的关键酶1-脱氧木酮糖5-磷酸还原异构酶。coli.5。非甲羟戊酸途径的生物合成中间体2-C-甲基-D-D-胆甾醇4-磷酸被一种新的酶2-C-甲基-D-D-胆甾醇4-磷酸胞苷酰转移酶转化为4-（胞苷5 '-二磷酸）-2-C-甲基-D-D-胆甾醇。上述4-（胞苷5 '-二磷酸）-2-C-甲基-D-腺苷酸被一种新的酶4-（胞苷5'-二磷酸）-2-C-甲基-D-腺苷酸激酶转化为它的2-磷酸衍生物。将上述磷酸酯衍生物转化为2-C-甲基-D-β-2，4-环二磷酸酯。

We have obtained the following results.1. Labeling experiments proved that novobiocin produced by Streptomyces niveus was biosynthesized by the nonmevalonate pathway.2. The terpene moiety of BE-40644 produced by Actinoplanes sp. was biosynthesized by the mevalonate pathway, but the cell membrane component, menaquinone, was produced by the nonmevalonate pathway.3. HMG CoA reductase was purified from Streptomyces sp. CL190aeriouvifer and its relevant gene was cloned.4. The key enzyme of the nonmevalonate pathway, 1-deoxyxylulose 5-phosphate reductoisomerase, was purified from E. coli.5. A biosynthetic intermediate of the nonmevalonate pathway, 2-C-metllyl-D-erythrito1 4-phosphate, was converted to 4-(cytidine 5'-diphospho)-2-C-methyl-D-erythrito1 by a new enzyme, 2-C-methyl-D-erythritol 4-phosphate cytidylyltransferase.6. The above mentioned 4-(cytidine 5'-diphospho)-2-C-methyl-D-erythritol was converted to its 2-phosphate derivative by a new enzyme, 4-(cytidine 5'-diphospho)-2-C-methyl-D-erythritol kinase.7. The above mentioned phosphate derivative was converted to 2-C-methyl-D-erythritol 2, 4-cyclodiphosphate.